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Comments 22701 to 22750:

22701. Andy Skuce at 13:27 PM on 21 October 2016
       No longer taken seriously, we're seeing the last gasp of climate denial groups
       

       nigelj, we previously covered the debacle of the collapse of Northern Rock and how Ridley's catastrophic risk management was to blame. 

22702. nigelj at 13:08 PM on 21 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       Art Vandelay @8, some media do indeed have rather alarmist titles on climate change, or get the facts wrong. No use pretending otherwise. 

       However The Guardian mostly do a pretty accurate job in my experience and without too much hype. The examples in the article tend to be the exception.

       And it goes both ways. Some media over emphasise skeptical climate change stories with bold headlines like "new study proves climate change is not happening / over rated / is a scam (etc)." The new study invariably either says nothing of the sort, or is just some think tanks ridiculous, opinion, as opposed to a peer reviewed study.

       The public most likely read between the lines, and know the truth is closer to the sober, measured reports by the IPCC. And this is more than concerning enough.

22703. Art Vandelay at 12:36 PM on 21 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       A bit of alarmism might help to propagate a message, but when it amounts to misinformation there's no doubt that the cause is undermined. 

       Just as every cold snap isn't proof that the climate isn't warming, every tornado, flood and tropical storm isn't caused by climate change, and nor is a day, month or a year of record high temperature empirical evidence thereof. 

       Of course, the media wants a climate change story, but unlike most news, climate change is not a 24hr phenomenon.  This, I think, is what makes "climate change" difficult for news media to sell as a news story, without introducing misinformation, either deliberately or by unavoidable inference. 

       And even when climate related news is scientifically factual it's often presented under the banner of an alarmist headline, such as, "Arctic Cities Crumble as Climate Change Thaws Permafrost", and often with a distressing  photograph for added visual effect and impact. 

       What needs to be appreciated is that the media needs to sell stories to make money, and climate change is a very long and mostly boring story.  

22704. nigelj at 11:16 AM on 21 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       The Guardian does occasionally highlight worst case scenarios a bit much. The mainstream media can’t help themselves as they know this gets people buying newspapers.

       However overall in my experience, all praise for the Guardian for mostly getting it right with good, restrained, reliable, balanced coverage on climate change.

22705. nigelj at 11:10 AM on 21 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       Denisaf @ 5, I dont find the article remotely confusing.

       You seem upset the article doesn't deal with how to build sea walls. This is because this particular  article is about climate science, if thats ok with you. Climate science is actually quite important, as is how it's reported in the media.

22706. nigelj at 10:56 AM on 21 October 2016
       No longer taken seriously, we're seeing the last gasp of climate denial groups
       

       Lionel @2, thanks for the review link. It was most interesting, I totally agree with it, and it confirms what I said. Ridley is an extreme libertarian and his book is on “evolution” is a sort of "trojan horse" for his libertarian views on completely unrelated matters.This is what annoyed me in particular. Some of his views are reasonable, but most aren't.

       I read somewhere in the mainstream, responsible part of the media that Ridleys company Northern Rock went bankrupt. The article noted Ridley had previously argued for minimal financial regulation and was quite successful at this goal. He also rubbished government bail outs of financial institutions. Then Northern Rock, (which he managed) went bankrupt and this was largely his own fault due to a high level of risk taking,  yet he blames everyone else, and asked for a big handout from the tax payer to bail his company out. The arrogance and hypocrisy is breath taking.

       Regarding Ridley and climate change, he subscribes to every sceptical argument imaginable including the truly silly ones, which just goes to show you can have an advanced degree in biology and still embrace ludicrous notions.

22707. Tom Curtis at 07:11 AM on 21 October 2016
       Global warming theory isn't falsifiable
       

       kevanhashemi @73, considering the preindustrial condition in which there is close to equilibrium between CO2 fluxes into and out of the atmosphere, and assuming the relative ratio of C₁₄ in the respective pools as specified by you @69, then a gross flux 28.25 petagrams of carbon per annum (PgC/yr) into the ocean from the atmosphere would carry 32.95 Kgs of C₁₄ with it.  At the same time, a gross flux of 28.25 PgC/yr from ocean to atmosphere would carry 26.36 Kgs of C₁₄ with it.  The net flux would be 6.59 Kgs of C14 from atmosphere to ocean, with zero net flux in CO2.

       This back of the envelope calculation ignores that C₁₄ has a slight bias in its flow from atmosphere to ocean over its flow from ocean to atmosphere (due to its slower mean velocity at a given temperature due to its greater mass), radioactive decay and any net flux in C₁₄ from the atmosphere/biosphere exchange.  It also ignores the fact that, in the prindustrial state, there is a slight bias of outgassing to dissolving of CO2 from the ocean (about 2%), which is compensated by (mostly) soil carbon eroded into the ocean.

       The key point, however, is that the gross flux is approx. 35% of the true value as shown by the IPCC AR5 diagram.  Therefore, the back of the envelope calculation gives us no reason to think the fluxes shown by the IPCC AR5 diagram are underestimates.

       As it happens, the C₁₄ concentration in the surface ocean is approx 95% of that in the atmosphere, not 80%.  Plugging in that value would result in an overestimate from the back of the envelope calculation, but not so large as to call the IPCC figures into question.  If you do want to call them into question you need to take account of the differential flux of C₁₄ due to its increased mass, the influx of low C₁₄ organic matter from soils, the fact that the C₁₄ concentration of the surface ocean varies by location and therefore it matters crucially where the exchanges occur, and all the various complications that were taken into account in the scientific papers on which the AR5 depended in determining its fluxes.

22708. william5331 at 04:43 AM on 21 October 2016
       No longer taken seriously, we're seeing the last gasp of climate denial groups
       

       This is always the problem.  You need the disaster first so that the deniers can't make this argument.  The trouble is, that in this case we are likely to flip the climate to a new state and with no chance of moving it back to the present setting for eons.  Let's hope for some smaller but highly scary disasters to shake the world to its core before we reach the tipping point.  A new study from New Zealand suggests that at about 425ppm Carbon dioxide, the climate begins to change and doesn't revert even when Carbon dioxide concentrations go down.  There is absolutely no chance we will not pass this possible threshold by a large margin.

22709. kevanhashemi at 03:51 AM on 21 October 2016
       Global warming theory isn't falsifiable
       

       Corection: "net transport of 5.65 kg of carbon-14", not Pg.

22710. kevanhashemi at 03:50 AM on 21 October 2016
       Global warming theory isn't falsifiable
       

       Dear Tom,

       I missed this earlier. You say "Therefore, at equilibrium, and ignoring radioactive decay, 5.65 Petagrams of Carbon leave the atmosphere, which tells us nothing about the net flux." You are forgetting that a like amount of carbon replaces the 5.65 Pg at equilibrium, and it also contains carbon-14. You need a net transport of 5.65 Pg of carbon-14 out of the atmosphere every year. What is the concentration of carbon-14 in the place that this 5.65 Pg is going to? Suppose it's 0.96 ppt, then the transport is 25 * 5.65 Pg/yr = 140 Pg/yr.

       Yours, Kevan

22711. John Hartz at 00:54 AM on 21 October 2016
       No longer taken seriously, we're seeing the last gasp of climate denial groups
       

       Recommended supplemental reading:

       Donald Trump Is the First Demagogue of the Anthropocene by Robinson Meyer, The Atlantic, Oct 19, 2016

22712. Lionel A at 20:43 PM on 20 October 2016
       No longer taken seriously, we're seeing the last gasp of climate denial groups
       

       nigelj and others may be interested in a review by Jerry Coyne of what is at guess the Ridley book indicated above:

       My review of Matt Ridley’s new book, “The Evolution of Everything”

22713. denisaf at 14:23 PM on 20 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       This confusing discussion in a selected press contributes little to the debate amongst authorities about measures to cope with the impact of climate change. The action being instigated in New York, London and the Netherlands to cope as much as possible with sea level rise and storm surges are examples of what should be given more publicity.

22714. nigelj at 11:37 AM on 20 October 2016
       No longer taken seriously, we're seeing the last gasp of climate denial groups
       

       Good article. I recently bought Ridley’s book on evolution on impulse, never having heard of the guy. The back cover looked interesting and appeared to be about evolution as applied to organisations.

       The theory of evolution applied to organisations was actually rather weakly developed, but many of the chapters were nothing to do with evolution, and totally about climate change denialism and quite extreme neoliberal theories about the virtues of private education, deregulation, and neoliberal economics.There was nothing about this on the back cover, so the title and back cover was misleading.

       His ideas on climate make very selective use of evidence, and so do his ideas on economics and social issues. I know because I'm reasonably familar with some of these issues. So Ridley is true to form I guess.

       Most of what the book said on economics and social issues was utter nonsense. I put the book in the rubbish after a few chapters.

22715. scaddenp at 09:59 AM on 20 October 2016
       2016 SkS Weekly Climate Change & Global Warming News Roundup #42
       

       Good point Tom. Maybe a way to have an equitable climate and still be able to fly.

22716. Jamie at 09:50 AM on 20 October 2016
       Climate's changed before
       

       I really enjoyed that this article had scientific information to back up some of its claims even if some of the links were not the most concrete sources. I agree with the article saying that the climate has changed before; there is too much scientific evidence for anyone to claim that it has not. One example I can think of is ice cores. I believe this article could have gone more in depth when explaining its points. However, I also believe humans have some impact on increasing the rate of climate change. The anthropogenic carbon dioxide emissions are increasing at such a rapid rate, I have no choice but to believe they will influence. I have posted a paper that I think will help sway some people to believe that humans do have an effect on climate change. 

       Zhang XB (2007) "Detection of human influence on twentieth-century precipitation trends" Nature 448, 461-465. 

       Abstract: "Human influence on climate has been detected in surface air temperature(1-5), sea level pressure(6), free atmospheric temperature(7),tropopause height(8) and ocean heat content(9). Human-induced changes have not, however, previously been detected in precipitation at the global scale(10-12), partly because changes in precipitation in different regions cancel each other out and thereby reduce the strength of the global average signal(13-19). Models suggest that anthropogenic forcing should have caused a small increase in global mean precipitation and a latitudinal redistribution of precipitation, increasing precipitation at high latitudes, decreasing precipitation at sub-tropical latitudes(15,18,19), and possibly changing the distribution of precipitation within the tropics by shifting the position of the Intertropical Convergence Zone(20). Here we compare observed changes in land precipitation during the twentieth century averaged over latitudinal bands with changes simulated by fourteen climate models. We show that anthropogenic forcing has had a detectable influence on observed changes in average precipitation within latitudinal bands, and that these changes cannot be explained by internal climate variability or natural forcing. We estimate that anthropogenic forcing contributed significantly to observed increases in precipitation in the Northern Hemisphere mid-latitudes, drying in the Northern Hemisphere subtropics and tropics, and moistening in the Southern Hemisphere subtropics and deep tropics. The observed changes, which are larger than estimated from model simulations, may have already had significant effects on ecosystems, agriculture and human health in regions that are sensitive to changes in precipitation, such as the Sahel."

22717. Glenn Tamblyn at 09:40 AM on 20 October 2016
       2016 SkS Weekly Climate Change & Global Warming News Roundup #42
       

       Tom
       
       Sounds like there is still a way to go, but promising.
       
       "We report an electrocatalyst which operates at room temperature and in water for the electroreduction of dissolved CO2 with high selectivity for ethanol. The overpotential (which might be lowered with the proper electrolyte, and by separating the hydrogen production to another catalyst) probably precludes economic viability for this catalyst, but the high selectivity for a 12-electron reaction suggests that nanostructured surfaces with multiple reactive sites in close proximity can yield novel reaction mechanisms. This suggests that the synergistic effect from interactions between Cu and CNS presents a novel strategy for designing highly selective electrocatalysts. While the entire reaction mechanism has not yet been elucidated, further details would be revealed from conversion of potential intermediates (e. g. CO, formic acid and acetaldehyde) in future work."

22718. Tom Curtis at 08:49 AM on 20 October 2016
       2016 SkS Weekly Climate Change & Global Warming News Roundup #42
       

       scaddenp @3, you are correct that no sequestration is involved, and I doubt pumping ethanol into subterainean caverns would be a suitable method of sequestration.

        The importance of this process is that it produces a liquid fuel.  Liquid fuels have the advantages of easy storage, and high energy intensity relative to renewables which make them very suitable for vehicles in a way that hydrogen (because of storage issues) and electricity (due to limited storage capacity in vehicles) are not.  Ease of storage is also a factor in back up generators.

       Further, in a way the energy efficiency has limited relevance.  If we are to build an all renewable system, then we will need to build a significant overcapacity so that when the renewable sources are not operating at full capacity (most of the time), they can still provide 100% of standing energy needs.  That means for much of the time excess energy will be generated with no standard use.  That energy is essentially free, and can be applied to any process that can operate intermittently to good effect; ie, generating hydrogen from water, and now ethanol from water.  Because the energy is essentially free, convenience of storage may be the determining factor as to which of the two fuels is best to use (and certainly is for transport).

22719. scaddenp at 07:55 AM on 20 October 2016
       2016 SkS Weekly Climate Change & Global Warming News Roundup #42
       

       Sorry Tom but I dont get it. There is no sequestration of CO2 - it gets released again the moment it is burnt. You have to use Carnot cycle to get useful work back so it doesnt seem to be even a particular efficient way to store energy. You lose 35% of the energy converting electricity to ethanol, and then will lose at least 35% more as waste heat converting the ethanol to work. Batteries are more like 90% efficient, pumped hydro around 70%.

22720. Tom Curtis at 07:44 AM on 20 October 2016
       2016 SkS Weekly Climate Change & Global Warming News Roundup #42
       

       Popular Mechanics: Scientists Accidentally Discover Efficient Process to Turn CO2 Into Ethanol

       The title almost says it all.  The key points are that the process takes CO2 and H2O from the atmosphere, and coverts it to Ethanol at a claimed 65% energy efficiency.  The ethanol can then be used as a fuel for power plants and vehicles.  It is further claimed the process is cheap and scalable, which if true should mean large scale prototypes should be available in approx 5 years, and commercial variants in 10 or so.

       If this pans out, it is the best news I have seen for quite some time.

       The scientific paper discussing the discovery is also available.

22721. dana1981 at 00:16 AM on 20 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       Thanks chriskoz.  Climate Feedback hasn't looked at any of ours yet.

22722. chriskoz at 11:27 AM on 19 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       I'm happy to find out that both articles found to be unscientific in this review:

       False alarmism by Wadhams and Denialism by Lovelock were not written by our SkS authors dana1981 nor John Abraham. I don't know if their writing have been scrutiniesd here but for my part, I praise them because I always find them accurate and informative. Thank you Dana & John for your contribution to both TheGardian and SkS.

22723. rocketeer at 08:05 AM on 19 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       I should mention the Callendar prediction was made in 1938.

22724. rocketeer at 08:03 AM on 19 October 2016
       Insight into the scientific credibility of The Guardian climate coverage
       

       "[Lovelock] argues that “CO2 is going up, but nowhere near as fast as they thought it would. The computer models just weren’t reliable.”

       This is silly.  The CO2 increase is entirely a function of how much fuel we burn.  You can certainly construct a model to predict it, but it is only going to be as good as the fuel consumption forecast which is not a scientific question.  Whether the projections are high, low or precisely correct has no bearing on the science of climatology.  G.S. Callendar didn't think we would get to 400 ppm before the 23rd Century, but he predicted that the Earth would be about 1.0 C warmer than preindustrial times at that point.  So he was off by 200 years on the timeline, but within a tenth of a degree C on the effect.  So was that a reliable prediction or not?

22725. PluviAL at 02:36 AM on 19 October 2016
       Finance for deep-rooted prosperity is coming
       

       This is the most positive story I have seen all year, and ever on this Sk S. These are solution oriented considerations. Although I am a UC MBA, I had not given sufficient weight to macroeconomic measures, even though this is really what has made Wind and PV advance so well. The generality that this is what will advance societies, rich and poor, is understated. Beyond knowledge and freedom to innovate, the biggest driver of economic progress is energy, which has meant CO2. By planning to reach beyond CO2 for energy as we advance all societies, a truly wonderful era is arriving. We can do it if we want to.

       Thanks for the positive news.

22726. kevanhashemi at 00:15 AM on 19 October 2016
       Global warming theory isn't falsifiable
       

       Dear Tom, Thank you very much. For some reason I was worried about that calculation. Looking at the diagram: of order 40,000 Pg carbon interacting with the atmosphere, I agree that's close enough. I think I assumed that the carbon-14 concentration was parts per trillion atomic, not parts per trillion by mass. I will have to check, but if it's by mass, then thank you for pointing out the correction. Yours, Kevan

22727. BBHY at 22:19 PM on 18 October 2016
       Hillary Clinton and Al Gore talk climate and energy in Miami
       

       We need to make progress on the climate problem as quickly as possible. We cannot afford to wait for the perfect politician, the perfect political climate, or the perfect technology breakthrough. We have to push forward right now, with the best that we have available right now.

22728. Tom Curtis at 14:49 PM on 18 October 2016
       Global warming theory isn't falsifiable
       

       kevanhasemi @69, using the figures provided by this wikipedia article, I calculate the range of the Mass of C₁₄ atoms created annually and globaly to be 6.14-7.04 (median 6.59) Kgs.  However, C₁₄ has an atomic mass of 14, compared to the atomic mass of 12 for atmospheric Carbon on average.  To calculate the rate of transfer of carbon atoms generally from those of C14, you would need to do it on a per particle basis, or apply an adjustment to bring the weighted C₁₄ mass in line to that of C₁₂.  By my calculation, that reduces the C₁₄ weighted mass to 5.65 Kg.  Therefore, at equilibrium, and ignoring radioactive decay, 5.65 Petagrams of Carbon leave the atmosphere, which tells us nothing about the net flux.

       That amount compares to the combined gross flux of 203.3 PgC/annum shown in the IPCC AR5 carbon cycle illustration, or a net flux (excluding that from fossil fuels and volcanoes), of 4.9 PgC/annum:

       

        

       That is close enough to the expected figure that there is no evident problem for the figures shown.  The discrepancy can be more than made up for by dillution of atmospheric C14 abundance by the exchange with the ocean, and by volcanic outgassing.

22729. raindog at 14:23 PM on 18 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       Tom Curtis #10 I am a bit concerned about the interpretation of "very serious and dangerous threat to humanity". It appears to me that the phrase could mean many things and different things to different people. The survey is indeterminate in this respect. As it stands, it is not clear to me that it excludes the possibility of extinction. Does this phrase have some more or less standard meaning in science?

22730. raindog at 14:03 PM on 18 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       scaddenp #11 Yes, I can see why Gavin might be exasperated.

       I understand the "committment"; I think there are reasons to doubt that it will/can be carried out (as I indicated above #9). And, if not, then :

       Many aspects of climate change and associated impacts will continue for centuries, even if anthropogenic emissions of greenhouse gases are stopped. The risks of abrupt or irreversible changes increase as the magnitude of the warming increases. {2.4}

       [Climate Change 2014 Synthesis Report, IPCC http://www.ipcc.ch/pdf/assessment-report/ar5/syr/SYR_AR5_FINAL_full_wcover.pdf]

22731. raindog at 13:39 PM on 18 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       Tom Curtis #10 Thank you very much for the clarification/correction. I see that it is very easy for someone new to this discussion to go astray. 

       I would only add that this situation is already somewhat of a catastrophe for some of us ( as I watch the current king tide bring the sea to within 10' of my back door and see corals dead or dying everywhere ...).

22732. kevanhashemi at 11:34 AM on 18 October 2016
       Global warming theory isn't falsifiable
       

       Also, I would greatly appreciate someone checking observations (1) through (7) above. For example, I had to multiply 2.0 carbon-14 atoms per second per centimeter squared by a bunch of numbers to get 7.5 kg/yr for the entire Earth, which I am rounding to 8 kg/yr. What if I'm off by a factor of ten? I have checked and checked, by I could be making the same mistake over and over again. Yours, Kevan

22733. scaddenp at 08:21 AM on 18 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       Raindog - Gavin gets pretty exaseperated by misrepresentation of his point of view. See his response at Realclimate on similar point.

       "I understand the "irreversible", in this context, to mean something similar to "cannot be controlled by human efforts" (e.g., geo-engineering)."

       I think that the papers I pointed to earlier would suggest that we are committed to 2degree warming. However, I dont see evidence let alone consensus for any warming that is not reversible by simply stopping emitting CO2. I dont think that is even  geoengineering.

22734. Marina Kingston at 07:21 AM on 18 October 2016
       Hillary Clinton and Al Gore talk climate and energy in Miami
       

       What do you think about Hillary's program about student loans (5 Student Loan Promises From Hillary Clinton - Forbes)? Sometimes I begin to doubt her competence!

       Moderator Response:

       [PS] Totally offtopic. Plenty of other sites where people are happy to talk politics. On this topic, only comments on climate policy pertinent to the above article may be discussed.

22735. kevanhashemi at 01:14 AM on 18 October 2016
       Global warming theory isn't falsifiable
       

       Dear Glenn,

       Thank you for your answer. I'm not sure why my site refused your comment, but I apologise for the inconvenience that must have caused you. I will check the comment settings.

       Which of the following facts to you dispute?

       (1) Carbon-14 is produced in the upper atmosphere at roughly 8 kg/yr.

       (2) 1 in 8000 carbon-14 atoms decays every year. Therefore, for equilibrium, there must be roughly 64,000 kg of carbon-14 on Earth.

       (3) There are only 800 kg of carbon-14 in the atmosphere. (800x10^12 kg of carbon in the atmosphere, 1 ppt is carbon-14)

       (4) Somewhere on Earth, other than the atmosphere, there is 63,200 kg of carbon-14.

       (5) Every year, 8 kg of carbon-14 migrate from the atmosphere to wherever the rest of it is.

       (6) Whatever atmospheric carbon-14 does, it does in the company of one trillion atmospheric carbon-12 atoms, because carbon-14 and carbon-12 are chemically identical.

       (6) The concentration of carbon-14 in the deep ocean is 80% of the concentration in the atmosphere. The concentration in the Earth's biomass is 99% of the concentration in the deep ocean.

       If you accept the above observations, I suggest you ask yourself how can 8 kg of carbon-14 move out of the atmosphere every year? 

       As to your suggestion that multiple reservoirs change the picture in a significant way: you are incorrect. Two- and three-reservoir systems are easiy to simulate in an Excel spreadsheet, so if you disagree, please prove me wrong. Or you can consult the Arnold et al. paper linked to below for their proof that the complexity of the reservoir makes not difference to the fundamental behavior of the combination.

       http://www.hashemifamily.com/Kevan/Climate/Dist_C14_Nature.pdf

       Where does the 8 kg of carbon-14 go? By what chemical process does it get to wherever it goes? Please answer these specific questions.

       Yours, Kevan

       Moderator Response:

       Link updated[GT]

22736. Dikran Marsupial at 17:40 PM on 17 October 2016
       Global warming theory isn't falsifiable
       

       Here is the comment I posted on Kevan's earlier blog post (where it seemed more relevant), which concludes:

       "But the doubling of the carbon-14 concentration by bomb tests amounts to a gigantic experiment upon the atmosphere, and this experiment turns out to be profoundly revealing when it comes to estimating the effect of human CO2 emissions upon the climate."

       Unfortunately carbon-14 from bomb tests tells you almost nothing about the effect of human CO2 emissions upon the climate. This is because the decay of bomb carbon-14 can only tell you about the residence time of carbon in the atmosphere (the average time a particular molecule of CO2 remains in the atmosphere before being transferred to another reservoir) but not the adjustment time (the time taken for atmospheric CO2 to respond to changes in the sources and sinks - essentially the characteristic timescale of the decay of atmospheric CO2 should we cease all anthropogenic emissions today). The residence time for CO2 is not equal to the adjustment time because of the vast exchange fluxes that constantly exchange CO2 between reservoirs, but this is a straight swap, so it doesn't change atmospheric concentrations. 14C has a short residence time, but mostly because it is just being exchanged with 12C and 13C from the oceans and terrestrial biota. This is a somewhat counterintuitive idea that is often misunderstood, which is why I wrote a paper about it,

       Gavin C. Cawley, On the atmospheric residence time of anthropogenically sourced carbon dioxide, Energy & Fuels, volume 25, number 11, pages 5503–5513, September 2011.

       which you can find here:

       http://pubs.acs.org/doi/abs/10.1021/ef200914u

       preprint here:

       http://theoval.cmp.uea.ac.uk/publications/pdf/ef2011a.pdf

       I wrote a blog article about it for SkS, which you can find here:

       http://www.skepticalscience.com/essenhigh_rebuttal.html

       The residence time is not controversial, and estimates range from about 4 years to about 20. The adjustment time is much longer 50-200 years for the initial phase, but the decay has a long tail.

22737. Tom Curtis at 16:19 PM on 17 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       raindog, in March, 2009 Michael Tobis sketched a schematic graph of the distribution of scientific opinion on the consequences of Business As Usual emissions.  In January, 2010, he published this cleaned up version:

       

       The important point for your discussion @5 and @8 is that the official consensus position, ie, that of the IPCC is for "substantial cost" and that views of iminent catastrophe are to be found among a minority of climate scientists.  Views of imminent extinction are so rare among climate scientists as to not even make it on the chart.  Since 2010, evidence has tended to show the long tail of climate sensitivity (and hence the probability of extreme upper range temperature predictions) have reduced, which would if anything, compress the right hand side of the above distribution.

       For more exact information on the distribution of scientific opinion, we must turn to von Storch and Bray's series of surveys of climate scientists (which despite what I identify as biases from the authors being reflected in the wording of some of the questions, remains the best available).  Their most recent survey includes among many others, the following question:

       Figure 88. (v043) How convinced are you that climate change poses a very serious and
       dangerous threat to humanity? 

       Possible responses were on a scale, showing "not at all 1 2 3 4 5 6 7 very much".  The responses, in order and reported as a percentage, were 2.194, 3.108, 3.291, 5.667, 13.53, 26.14, and 46.07.  That indicates the majority scientific opinion is that climate change poses a very serious and dangerous threat, but that falls far short of an exinction level threat (which unfortunately it was not possible to indicate).  That less than 50% are "very much" convinced of the possibility of a "very serious and dangerous threat", however, shows it to be very unlikely that many (if any) are convinced it is an extinction level threat.

       More specifically to your points, the consensus on Arctic Sea Ice is that it has no tipping point, so that even if completely removed, it would rapidly return of Arctic SSTs were Arctic tempertures dropped to normal values (ie, 1960s values).  On methane, the majority opinion among relevant scientists is that there is no "clathrate bomb".  And so on.  There are some credible "runaway processes" but they will, as yet, have minimal overall impact.

       With regard to your specific quote @8, the threat of "runaway climate change", contrary to appearences, was raised neither by Gavin Schmidt nor the "recent research".  It is introduced without basis by the author, and passed of as being on the authority of Schmidt and/or the research in a dishonest fashion.  The article proves mostly that there is now a niche in more left leaning media, and on some blogs, for authors who want to feed a diet of pure catastrophism which is unjustified by the scientific consensus.

22738. raindog at 12:06 PM on 17 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       RedBaron #7 I agree with you, and with the combination of your 3 approaches.

       What I see is a lack of will to actually take the actions necessary, on the scale and within the time required, among the folks who would make the difference (roughly those earmarked by Anderson).

       no-dapl ... leave it in the ground

22739. raindog at 11:50 AM on 17 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       scaddenp#6 I think that there is significant consensis among researchers (and, perhaps, even policy makers — "By all accounts, countries have acted with remarkable haste in ratifying the Paris Agreement") that, even if we are able to limit warming to 2°C (which seems unlikely), we have already triggered significant "positive feedback" conditions (such as Arctic melting, releases of methane, acidification of the ocean, extinction of other species, etc.) that will contribute to climate change in a sort of snowball effect that cannot be controlled or reversed.

       [Gavin Schmidt, director of Nasa’s Goddard Institute for Space Studies]... is the highest-profile scientist to effectively write-off the 1.5C target, which was adopted at December’s UN summit after heavy lobbying from island nations that risk being inundated by rising seas if temperatures exceed this level. Recent research found that just five more years of carbon dioxide emissions at current levels will virtually wipe out any chance of restraining temperatures to a 1.5C increase and avoid runaway climate change. (https://www.theguardian.com/environment/2016/aug/30/nasa-climate-change-warning-earth-temperature-warming)

       It seems that even a commitment to 2°C may be too little, too late (as it appears is already the case for some small island & low-lying nations already suffering effects of sea-level rise, for example).

       I understand the "irreversible", in this context, to mean something similar to "cannot be controlled by human efforts" (e.g., geo-engineering).

       Perhaps we should just talk about it for another 5 years and see what happens ... ?

       ~~~

       no dapl

22740. BC at 11:49 AM on 17 October 2016
       2016 SkS Weekly Climate Change & Global Warming News Roundup #42
       

       The first link on the methane spike doesn't work correctly for me.

       Thanks for compiling this list - I always scan through it and find lots of interesting reading.

       Someone commented last week about missing the monthly article that shows a plot of the global temperature 'Tracking the 2 degree limit'. I miss it too

       Moderator Response:

       [BW] Thanks for the heads-up, BC! I fixed the link.

22741. RedBaron at 10:46 AM on 17 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       @raindog,

        There is a lot of potential for McPherson to be right. However, having watched several of his lectures, the one glaring gap that he certainly overlooks is humanity's ability to affect stabilizing feedbacks. He is correct in so much as right now almost all those human influenced stabilizing feedbacks are degraded as a continuing result of our influence.

       However we do have an equally large potential for positively affecting them. In other words, humans have equal ability to restore ecosystem function as degrade ecosystem function. Humans are just as capable of planting a forest as slash and burning a forest. We are just as capable of creating a wetland as draining one. We can as easily restore a savana or prairie as plow it and plant corn. We just don't happen to be by and large doing it at the moment. In fact we have to spend lots more effort, money and energy keeping those ecosystems non-functional as we would have to spend to restore those ecosystem functions.

       "We try to grow things that want to die, and kill things that want to live. That is pretty much how (industrial) agriculture functions." Colin Seis

       In my honest opinion McPherson could be right, but it is not necessarily a given. There is no requirement that humans interact with the biosphere the way we ciurrently do now. But I also believe he is correct, conditional to if we don't radically and fundamentally change that interaction.

       That would include a 3 way approach, reducing fossil fuels, Biological Carbon Capture and Storage (BCCS) in agriculture, and large scale ecosystem recovery projects. The more I study it, the more I am convinced it can work, but would require all 3. I am almost certain that focusing only on fossil fuel emissions will ultimately fail due to exactly what McPherson talks about in his lectures. Too much much CO2 in the atmosphere already, and too much heating already stored in the system, taking too long to get rid of without humanity making a concious and real effort to help instead of hinder recovery.

22742. scaddenp at 07:09 AM on 17 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       I don't think McPherson's claims are based on published science. There have been studies of this, and you might like to look at this post on climate commitments though I suspect there may be more recent work.

22743. raindog at 06:21 AM on 17 October 2016
       Explainer: Paris Agreement on climate change to ‘enter into force’
       

       RE: #3: scaddenp, there are some, like Guy McPherson, who believe we have already passed "a point of no return" and face extinction. Others, like Kevin Anderson, think we are very late in the game here, but, perhaps, still can avert the most dire consequences of climate change if we take immediate and appropriate action. In videos and papers, he does make suggestions.

       I am not a scientist, but there does seem to be some validity to the idea that climate change may, at this time, be irreversible.

       Please correct me if I am wrong.

22744. nigelj at 06:22 AM on 16 October 2016
       Climate scientists published a paper debunking Ted Cruz
       

       William @2, politicians are notorious for dishonesty, and also having different stories for different audiences. They do this so often they probably end up not even realising they are doing, it or knowing what they really believe themselves.

22745. Bob Loblaw at 05:00 AM on 16 October 2016
       It's the sun
       

       BillN:

       I expect that your latter paragraphs, if not your whole post, will be deleted by the moderators. For someone who complains about others' tone, you seem to not hold yourself to the same standards. What you consider to be "reasonable" in your own posts is not considered reasonable by others here.

       In your post #1180, the full sentence is:

       Even though the FOV (Field of View) of the instrument picks up only a small fraction of the solar disk, so that the solar light intensity at the cone is only a small fraction of the full TSI, the instrument has to stay on for a while in order to come to thermal equilibrium when making a measurement (thermal equilibrium under loading is the basis for making the measurement).

       You may not have specifically stated that an adjustment is needed, but you did say (incorrectly) that the instrument does not measure the full disk, which certainly implies that something needs to be done about it. How would you get a proper reading of the full TSI from a partial measurement if you do not account for the partial measurement? Or were you just (incorrectly) implying that an assumption had been made that thought was unwarranted?

       Your use of the word "optical" implies much more than it should to the casual reader. I pointed out the very limited limited scope in which that term applied to the Eppley HF. If what I said was (to quote you) "exactly" what you meant, then that is what you should have said to begin with. I have not accused you of intentionally misleading anyone, but I have clarified the very limited scope in which your statement applies, so that casual readers will not take the wrong impression from what you have said.

       When you walk in here and start proclaiming your expertise, and acting as if we should only take your word on things, then you are making an argument from your own authority. I provided links to the group (PMOD) responsible for the surface-based pyrheliometer comparisons and the World Radiation Reference. I provided a link to a peer-reviewed journal paper describing the stability of the Eppley HF after space exposure. Tom Curtis has provided you with other links. You have not (as far as I can see) provided a single link to support any of your assertions - instead expecting us to believe you solely on the basis of your claimed expertise. Since you claim to have knowledge in these areas, surely you can back up your claims with some references?

       You are correct that SkS is a web site where individuals that can provide nothing more than a viewpoint are subject to critical reaction. People are expected to provide independent support of those opinions.

22746. RedBaron at 04:39 AM on 16 October 2016
       Climate scientists published a paper debunking Ted Cruz
       

       @2 William,

        You said, "Go figure. I wonder how many politicians are equally crassly dishonest."

       All of them? It's a job requirement!

22747. william5331 at 03:56 AM on 16 October 2016
       Climate scientists published a paper debunking Ted Cruz
       

       Seems somehow beneath our dignity to answer every ning nong that denies the evidence of his own eyes.  I suppose it has to be done.  I was talking to a climate change scientist a month or so ago in England.  He related an interesting story.  He was at a conference, not on climate change, in which one of the politicians (who shall remain nameless) was giving vent to the usual denyer story.  Purly be coincidence, this chap was seated beside the politician on the plane on the way back home.  They got talking about climate change.  The politician expressed the opinion that it was our most serious problem today.  Go figure.  I wonder how many politicians are equally crassly dishonest.

22748. PluviAL at 03:28 AM on 16 October 2016
       Climate scientists published a paper debunking Ted Cruz
       

       Scientifically, conservatives are grasping at straws, but politically they are wilding a sledge hammer: Americans (AND other car and high consupmtion people) don't want to hear the truth, if it means we have to work or sacrifice, and we are masters of self-deception. The question is can we be made to try harder than just a few more enlightened states carrying a backwards nation (world)? I say no, unless people can see solutions. We need to offer solutions before America can climb down from our delusions.

       As some may know I work toward solutions in my books and papers. I wish more scientifically minded people would join me. There are solutions if we think on scale, and seriously. Wind and PV solar are solid starts, but I think we need minimally 10 times more potency than those tools can offer. We can get 100 times that potency, and really much more.

22749. Bill N at 03:06 AM on 16 October 2016
       It's the sun
       

       Bob,

       You have mischaracterized what I have said on almost every count.

       The only thing you have corrected me on is that the FOV for these instruments encompasses the entire solar disk, which only serves to strengthen my argument that the solar light hitting the cavity wall will degrade it and cook any outgassing contamination on it.  I never said an adjustment must be made to account for what I thought was a limited FOV, so again you mischaracterize.

       I never said that there were any other optics besides the open aperture and the optical cavity, so again you mischaracterize.  You yourself said that the only room for optical change is the cavity reflectance (absorption ratio).  But that's exactly what I have been talking about, nothing more, nothing less.  It is the long term stability of this optical property under degrading environmental influences that is the question here.

       I did not feel the need to explain what "active cavity radiometers" are beyond the optical components being evaluated, assuming that interested readers here can Google this in a split second and get a lot more detail on them than what I could provide in writing.  So what's you beef here.

       Again you BS when claiming that I said the instrument developers did not consider stability.  I have stated here till I'm blue in the face that there is disagreement amongst the developers and users over what the stability is, even to the point that some think they can not be relied upon for long term TSI variability measurements.  So obviously this is a hot topic for them, as I have said again and again.

       Finally, I have made no claim whatsoever as to being an authority on space-based TSI measurements, so you last mischaracterization of me about this is a cheap shot.  My only "authoritity" is my general experience as an optical engineer flying spaceborne instruments, with of course then radiometry part of that experience (some of this covered solar measurements).

       So summarizing Bob, you're really a piece of work.

       After recieving so much vitriol about reasonably poised questions and thoughts by me, I decided to Google what other folks think about what is going on at ScepticalScience.  Wow!  It seems the world opinion is that this site is populated by a bunch of alarmist trolls (kids mainly) who engage in dirty tactics to voraciously defend their pseudo-scientific viewpoints, so that anyone who comes here with a differing viewpoint, no matter how reasoned, will not be treated fairly.  Well, that is certainly what I have experienced here (with a few exceptions).  So good bye.

22750. Bob Loblaw at 01:38 AM on 16 October 2016
       It's the sun
       

       I will try to keep this short for the moment, as it look as if BillN may be leaving.

       BillN has made several assertions about space-based measurements of TSI. I have not been involved in any space-based measurements, but I have a dozen year of experience in ground-based measurements of direct beam solar radiation using Eppley HIckey-Frieden (HF) cavity radiometers, of identical type to those that have been used in space. [All Eppley HF radiometers are built to the same space-rated specifications. I can't point to a peer-reviewed article that says so, so in a scientific paper I would have to reference this as "John Hickey, personal communication". He's the "Hickey" in "HF"...]

       Anyway, BillN has made several questionable assertions. I will respond to a few:

       • He refers to "optical stability". In the Eppley HF, the only "optics" are a black cavity that is fully-exposed to sunlight - no glass, no optics to focus sunlight, just an exposed cone-shaped receiver. The important "optical" characteristic of this receiver is its absorption ratio (or reflectivity, if you prefer). If that were to change, then stability would be affected, but all that cavity does is absorb solar radiation.
       • The radiometer also has a tube and calibrated orifice arrangment to limit the field of view. You may also call this "optics", if you like, but it's not as if there is a telescope or anything like that. It's much like limiting your field of view by holding a paper towel tube in front of your eye. It's fancier than that - black interior, etc., to limit stray light reflections, and a controlled area aperture at the end so that you get an exact field of view, but that's it.The view of the sun is completely unobstructed.
       • The field of view of the Eppley HF is slightly larger than the diameter of the sun, so BillN's assertion in comment #1180 that "Even though the FOV (Field of View) of the instrument picks up only a small fraction of the solar disk..." is simply wrong for the Eppley HF. For ground-based measurements, this means that the instrument also views a bit of scattered sunlight around the sun, but in space this will not happen. There is no adjustment for seeing a portion of the solar disk, as BillN has stated.
       • BiilN correctly refers to "active cavity radiometers", without explaning what they are. The Eppley HF can be operated either in active or passive modes. The principle of operation is that the cavity that absorbs solar radiation will heat up, which introduces a temperature gradient measured by a thermopile. In active mode, this heating is offset by an electrical heater, and by measuring the electrical heating rate you will know the solar heating rate. In passive mode, you measure the thermopile output caused by solar heating (no electrical offset), but periodically shade the instrument (no sun) and substitute a short period of electrical heating to check the calibration. The calibration results is used to convert the solar-heating output to irradiance. Ground-based observations using the HF will usually use passive mode (e.g. at the International Pyrheliometer Comparisons held every five years in Davos, Switzerland, where the World Radiation Reference is maintained. These IPCs (which have been happening since the 1960s) are a primary indicator of instrument stability in ground-based measurements.

       So, stability of an HF instrument depends on the absorption in the cavity remaining stable, and the electronics that measure the electrical heating remaining stable. There are no other "optics" involved.

       Rather than taking my word on any of this, HIckey, Frieden, and Brinker have reported on the stability of the Eppley HF after six years in space:

       Report on an H-F Type Cavity Radiometer after Six Years Exposure in Space Aboard the LDEF Satellite

       J R Hickey, R G Frieden and D J Brinker

       Metrologia, Volume 28, Number 3

       This is a 1990 paper, unforunately paywalled, but the abstract reports a 0.1% stability, but with a 0.1% uncertainty on that value. 0.1% of 1368 W/m²works out to less than 1.5 W/m². After accounting for global abedo (30%) and dividing by 4 (area of sphere vs. area of circle), this leads to an uncertainty of less than 0.25 W/m² in global absorbed solar radiation. Much less than the CO₂ forcing.

       BillN is wrong in implying that the developers of such instruments have not considered stability. Tom Curtis' post above also explains how examiniation of multiple instruments and multiple sources of analysis increases confidience in the readings of TSI.

       In short, BillN's implied position of infallible authority on matters of spaced-based TSI measurements is fallible.

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